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In this paper, we will discuss stability and reliability requirements of organic electronic devices and evaluate different encapsulation approaches enabling stable organic ultra-thin and stretchable devices. We highlight the differences in requirements and encapsulation approaches for applications, including organic light emitting diode (OLED) displays, OLED lighting, photovoltaics, and sensors. Stability and reliability requirements addressed in this paper cover light management, mechanical characteristics, chemical compatibility, form factors, and durability. While flexible organic electronic devices have already been demonstrated and commercialized, so far only prototypes of ultra-thin and stretchable devices have been demonstrated. The technological progress is promising and by identifying the gaps between prototyping and product realization, we intend to stimulate further research and development in this area.

Aims of the present investigation were: (i) to assess the prevalence of current smokers and relative smoking status among a large number of heroin addicts attending opioid-substitution therapy prevalence; (ii) to evaluate the relationship between the type (methadone, buprenorphine) and dosage of opioid substitution therapy and nicotine dependence. Three hundred and five (305) heroin addicts under opioid-substitution therapy were recruited at five Addiction Units. All participants completed a questionnaire assessing sociodemographic information, type and dose of opioid-substitution therapy, smoking history and status, Fagerström Test for Nicotine Dependence (FTND), and the Zung Self-Rating Depression scale (SDS). 298 subjects, out of 305 (97.2%) were smokers, with an average of 20.5 cigarette/day and a median FTND of 6. Our data confirmed the high prevalence of smokers among heroin addicts, the highest described in the literature to date among heroin addicts under substitution therapies, without any significant difference between methadone vs. buprenorphine therapy groups. There was no correlation between dose of methadone or buprenorphine and average number of cigarettes/day. Patients in substance abuse treatment very frequently smoke cigarettes and often die of tobacco-related diseases. Substance abuse treatment programs too often ignore tobacco use. We hope that these findings will help to incorporate smoking cessation in substance abuse treatments.

Silicon carbide films on silicon have been grown by annealing of pre-deposited C60 film on silicon at T = 900°C for 300 min. C60 molecules are confined on the surface during annealing by a non-volatile carbon layer produced by irradiation of the C60 film with an ion gun (Ar+ or Ga+). During annealing the C60 film confined in the irradiated areas forms SiC while the remaining C60 evaporates off. These results introduce a new method of direct patterning SiC structures on Si with submicron resolution.

We describe encapsulated passive matrix, video rate organic light-emitting diode (OLED) displays on flexible plastic substrates using a multilayer barrier encapsulation technology. The flexible OLED (FOLED™) displays are based on highly efficient electrophosphorescent OLED (PHOLED™) technology deposited on barrier coated plastic (Flexible Glass™ substrate) and are hermetically sealed with an optically transmissive multilayer barrier coating (Barix™ encapsulation). Preliminary lifetime to half initial luminance (L0∼100 cd/m2) of order 200 h is achieved on the passive matrix driven encapsulated 80 dpi displays; 2500 h lifetime is achieved on a dc tested encapsulated 5 mm2 FOLED test pixel. The encapsulated displays are flexed 1000 times around a 1 in. diameter cylinder and show minimal damage.

Thin film polycrystalline solar cells on low cost substrates offer an attractive path to large scale production of solar cells with the potential to generate electricity at 1$/W. SRI International has a propriety technology to deposit Si films in a reactor based on fluidized bed technology. The results presented in this paper show that, with a proper reactor design, Si films can be grown at rates of 7 μm/min and higher. Films are crystalline, with crystallite sizes higher than 20 μm. We have also evaluated the performance of SiO 2 diffusion barriers as a potential way towards the use of low cost substrates, such as metallurgical grade Si. Whereas SiO 2 layers of 0.1 μm are not sufficient to stop P diffusion from the substrate to the film, 0.7 μm layers are thick enough to accomplish this goal. The reactor configuration can be used for continuous and integrated cell/panel fabrication. At present we are building a first continuous reactor, and in this paper we present some preliminary considerations.

To meet increasing demand for electrical power using solar photovoltaics, millions of tons of solar-grade silicon costing 4 gas—an exothermic, fast, and complete reaction. SRI International routinely uses reactors that can produce at rates >20 metric tons per year (mty), and has licensed the technology to several companies. The Si product is completely separated from the by-product NaF by leaching or melt separation. With the direct use of industrially available Na, B and P levels in the Si product are 100 Ω·cm when purified reactants were used. The purity, electronic parameters, and solar cell efficiency of 15% indicate that this silicon is of solar grade and can be a key contributor in developing solar power markets.

Solar industry growth and a silicon feedstock shortage have spurred interest in thin silicon film photovoltaic (PV) technology. To reduce PV panel and electricity cost, technologies are needed with high deposition rates of high-quality Si film, scalability to large areas and integrated cell and panel fabrication. A new SRI International deposition technology based on fluidized bed reactor-chemical vapor deposition (FBR-CVD) takes advantage of the high heat and mass transfer in a FBR, and combines it with subhalide CVD chemistry with highly reactive species created in the reactor. The SRI's FRB design minimizes boundary layer thickness to achieve deposition rates as high as several microns per minute and good coating uniformity. The resulting silicon films are highly crystalline with 10–100 µm grain sizes over 5 cm2; with in-depth homogeneous resistivity, typically 0.1–5 Ω·cm, but up to 1000 Ω·cm obtained under some deposition conditions; and with bulk diffusion length >200 µm. The reactor configuration can be used for continuous and integrated cell/panel fabrication.

Reaction of C60 with Si at temperatures above 800°C is known to give SiC. Furthermore, treatment of vapor-deposited C60 films with a beam of Ar+ transforms the surface layer of C60 into a nonvolatile carbon deposit. Based on these two findings, we have developed a method for patterning SiC structures on silicon. C60 is first vapor deposited onto a clean Si surface. By rastering the ion beam on selected parts of the sample, we write a chosen pattern on the C60 film. Upon increasing the temperature to around 300–350°C, the C60 film remains only in the areas that were subjected to irradiation, while it evaporates off the remaining surface. During the subsequent annealing at 900°C, the modified C60 layer confines the underlying C60 on the silicon surface, allowing the formation of SiC. At shorter times, traces of the capping layer are visible at the edges of the irradiated zone. These results demonstrate the principle of fabricating lithographically patterned SiC structures on silicon without masking and etching processes and with the high lateral resolution possible with ion beams.

OLEDs are an ideal technology for electronic display applications. They are fabricated by depositing very thin films of organic materials at low temperatures (

Thin film barrier coatings for protecting Organic Light Emitting Diode (OLED) displays against the environment are extremely difficult to fabricate. The coatings must have extremely low water/oxygen permeability, no defects, cover several microns of topography, and be applied at temperatures below 100°C in a process that does not compromise the performance of the display. Vitex Systems has succeeded in depositing such coatings using an organic/inorganic, thin film multilayer structure termed Barix encapsulation. In this paper results on encapsulation of OLED test pixels and passive matrix displays will be shown. Lifetime and permeability tests conducted at high temperature and humidity demonstrate that this thin film coating can meet the necessary performance requirements for commercial OLED displays. Processing parameters, layer architecture and manufacturing techniques are analyzed and discussed. Thin film encapsulated displays are used to demonstrate the utility of the encapsulation technique.

At present flexible electronic devices are under extensive development and, among them, flexible organic light-emitting diode displays are the closest to a large market deployment. One of the remaining unsolved challenges is high throughput production of impermeable flexible transparent barrier layers that protect sensitive light-emitting materials against ambient moisture. The present studies deal with the adaptation of the atomic layer deposition (ALD) process to high-throughput roll-to-roll production using the spatial ALD concept. We report the development of such a process for the deposition of 20 nm thickness Al2O3 diffusion barrier layers on 500 mm wide polymer webs. The process uses trimethylaluminum and water as precursors at a substrate temperature of 105 °C. The observation of self-limiting film growth behavior and uniformity of thickness confirms the ALD growth mechanism. Water vapor transmission rates for 20 nm Al2O3 films deposited on polyethylene naphthalate (PEN) substrates were measured as a function of substrate residence time, that is, time of exposure of the substrate to one precursor zone. Moisture permeation levels measured at 38 °C/90% relative humidity by coulometric isostatic–isobaric method were below the detection limit of the instrument (

Irradiation of vapor-deposited C60 films with a KeV ion beam (Ar+ or Ga+) transforms the surface layer of C60 into a non-volatile carbon film. During the subsequent annealing at 900°C, the modified C60 layer confines the underlying C60 on the silicon surface, allowing the formation of SiC. With this method, patterned SiC structures on silicon with the high lateral resolution possible with ion beams are fabricated

We demonstrate full color, top emission, active matrix OLED displays on flexible stainless steel substrates. The 100 dpi QVGA displays are driven by LTPS TFT backplane with excimer laser annealed poly-Si. To our knowledge this is the world's highest resolution full color flexible AMOLED display on steel foil demonstrated to date. Encapsulation is by a multilayer thin film.

Fully encapsulated passive matrix, video rate, phosphorescent OLED displays on flexible plastic substrates using a multilayer barrier encapsulation technology are described. The flexible OLED (FOLED™) displays are based on highly efficient electrophosphorescent OLED (PHOLED™) technology deposited on barrier coated plastic film (Flexible Glass™ substrate) and are hermetically sealed with an optically transmissive multilayer barrier coating (Barix™ Encapsulation). Preliminary lifetime to half initial luminance (Lo∼100 cd/m2) of order 200 h is achieved on the encapsulated 80 dpi displays using a passive matrix drive at room temperature; 2500 h lifetime is achieved on a dc tested encapsulated 5 mm2 FOLED test pixel. The encapsulated displays are flexed 1000 times around a 1″ diameter cylinder and show minimal damage.